26) The area of the parallelogram having a diagonal 3 i → + j → - k → and a side i → - 3 j → + 4 k → i s (1) 10 3 (2) 6 30 (3) 3 2 30 (4) 3 30 Share with your friends Share 0 Manbar Singh answered this Dear Student, Let ABCD be the parallelogram and AC be its one of the diagonal.Let, AC→ = 3i^ + j^ - k^Let AB→ = i^ -3j^ +4k^Now, AB→ + BC→ = AC→ Parallelogram law of vector addition⇒BC→ = AC→ - AB→⇒BC→ = 3i^ + j^ - k^ - i^ -3j^ +4k^ = 2i^ +4j^ - 5k^Now, AB→ × BC→ = i^j^k^1-3424-5=i^15-16 - j^-5-8 + k^4+6=-i^ + 13j^ + 10k^Now, area of paralleogram ABCD = AB→ × BC→ = -12 + 132 + 102 = 270 = 330 Regards 0 View Full Answer Gaurang Yadav answered this rhn 0